Protected cutting device for sewing machines



Nov. 26, 1963 K. KLEEMANN ETAL 3, 1

PROTECTED CUTTING DEVICE FOR SEWING MACHINES Filed Dec. 31, 1959 4 Sheets-Sheet 1 Karl KL EEMA-NN lav/WW Nov. 26, 1963 KLEEMANN ETAL 3,111,921

C PROTECTED CUTTING DEVICE FOR sEwINC MACHINES Filed Dec. 31, 1959 I 4 Sheets-Shet 2 /N VENI'OR Wa/fer lRMSC/IER Karl KLEEMAN/V Nov. 26, 1963 K. KLEEMANN ETAL 3,111,921

PROTECTED CUTTING DEVICE FOR SEWING MACHINES Filed Dec. 31, 1959 I 4 Sheets-Sheet 3 3 FIG 5 IN VENT 0R Nov. 26, 1963 K. KLEEMANN ETAL 3,111,921

PROTECTED CUTTING DEVICE FOR SEWING MACHINES Filed Dec. 31, 1959 4 Sheets-Sheet 4 llw lm INVEN T 0 War/fer IR R Karl KLEE W W W I United States Patent 3,111,921 PROTECTED CUTTING DEVICE FOR SEWING MACHINES Karl Kleernann, Kaiscrslautem, and Walter Irmscher,

Mauer, near Neckargemund, Germany, assignors to G. M. Pfaif A.G., Kaiserslautern, Pfalz, Germany Filed Dec. 31, 1959, Ser. No. 863,179 Claims priority, application Germany Jan. 9, 1959 3 Claims. (Cl. 112-261) The invention relates to cutting devices for sewing machines and more particularly to a device for trimming the material such as lining on sewing machines where the cutter is pivotally movable out of its operating position and where during the turning movement of the cutter a cutter protector or shield is moved into its effective position proximate the turned out cutter. In this manner it is possible to accommodate the cutter shield in its idle position in a location which does not interfere with the sewing operations and from which it is merely moved in its own effective position during the turning of the cutter to its inoperative position.

It is an object of the invention to make the arrangement in such a manner that the cutter shield does not have any interfering effect when the cutter is in cutting position, and, besides that, it effectively covers the cutter when it is in turned out position.

In accordance with the invention this object is attained by a particular design and arrangement of the operating or actuating means guiding the cutter shield, where the particular novelty resides in that while shifting the cutter to inoperative position, it first runs ahead of the cutter shield which is arranged outside of the path of travel of the cutter and then the cutter shield arrives in the path of travel of the cutter, so that the cutter shield comes to rest in its effective position immediately before the cutter arrives in its inoperative position.

It has been found to be particularly suitable to arrange a cutting device having the characteristic features of the present invention in such known arrangements where a standard is provided which carries the work piece, and here the cutter can be swung out in a horizontal plane. In this connection the invention provides for the cutter shield being a unitary structure with a bearing sleeve which for the horizontal shifting of the cutter shield is rotatably journalled on the pivot axis and is provided with a mantle curve or cam, which during turning or pivotal movement cooperates with a pin and produces an axial movement of the cutter shield while a setting ring secured to the pivot axis carries a guide pin by means of which the cutter shield is moved along during the operation of the cutter.

Further features of the invention and details of the advantages obtained thereby will become apparent from the following description of an embodiment of the new cutting device illustrated in the attached drawings, particularly in connection with a standard sewing machine and in which:

FIG. 1 is a front view of the standard of a sewing machine of the standard type showing the cutter in position of operation,

FIG. 2 is a plan view showing the standard with the cutter in position of rest,

FIG. 3 is a side view showing the standard with the cutter in position of operation,

FIG. 4 is a perspective view of the cutter shield per se,

FIG. 5 is a rear view with the cutter in operating position,

FIG. 6 is a section taken along lines VIVI in FIG. 5, and

P16. 7 is a rear view showing the standard with the "ice cutter in position of rest and the cutter protector over it.

In PKG. 1 the pivot axis or shaft for the cutter is indicated at 1 which is driven for swinging movement in any desired manner known per se to cut the material being sewn. The operation of a cutter for which the shield in accordance with the invention is contemplated is described in the booklet entitled Pfaff 193-5-0225 published by the assignee of the present invention. On this pivot axis a cutter support 2 is clamped in position which is provided with an operating handle 2a and carries the cutter 3, with the support 2 and the handle 2a constituting the operating means for the cutter 3.

For turning the cutter 3 aside, the pivot shaft 1 is uncoupled in a known manner from its operating means so that the cutter together with the pivot axis or shaft 1 may be moved into the position in accordance with FIG. 2. A sleeve 4 constituting a support member which is provided with a mantle cam 5 constitutes a unitary structure with the cutter shield 6. The sleeve 4 with the mantle cam 5 defines a guiding conformation for the cutter protector or shield 6, which is journalled for pivotal movement and axial displacement upon the pivot axis 1.

A lock ring 7 which is provided with a drive pin 8 is adjustably clamped in position on the pivot axis 1. It limits the axial downward movement of sleeve 4 and of the cutter protector 6.

A helical spring 9 is hooked at one of its ends in the lock ring 7 and is secured at its other end to the standard 16 in a manner that it is tensioned by the turning of the cutter 3 into operating position and during the return movement of the cutter 3 into its position of rest or idleness, it facilitates the pivotal movement of the cutting device and of the cutter protector 6 as it is secured to the lock ring 7 which is clamped to the pivot shaft or axis 1.

Above the sleeve 4 there is provided a further helical spring 11 which is booked at one end into the sleeve 4 and at the other end into a bearing eyelet 12 so that pivotally moving the cutter into position of operation causes the cutter protector to be pressed against the standard 10 by the spring. The bearing eyelet 12 carries a plate 13 having a guide pin 14 which engages the mantle cam 5 and which, during pivotal movement of the cutter protector 6, effects raising or lowering of the sleeve 4 and of the cutter protector 6.

In accordance with the invention the cutter 3 secured to the cutter support 2 when moved manually by means of operating handle 2a first swings from its position of operating after unlocking of the pivot shaft 1 until the drive pin 8 on the lock ring 7 engages the lower end of the cutter protector or shield 6. The pivotal movement in this connection is caused by the spring which engages the lock ring 7.

As the drive pin 8 contacts the cutter shield 6 the cutter has already moved across the standard 10 and over the cutter shield 6 which is held against the standard by the spring 11, and only then the cutter shield 6 is carried along by the drive pin 8 and is simultaneously moved upwardly by the cam follower pin 14 which is in engagement with the mantle cam 5 on the rotating sleeve 4. As a result when the cutter is in idling position, the cutter shield is located before the edge of the cutter where it is held by the helical spring 9 against the force of the weaker spring 11 which engages the sleeve 4. For shifting the cutter to the idling position the operation handle 2a on the cutter support 2 is moved along a rocking path in the direction A into the position in accordance with FIG. 2.

If it is desired to bring the cutter 3 into its operative position in accordance with FIGS. 1, 3 and 5, the operating lever 2a is moved manually in the direction C against the force of the spring 9 into the position indicated in a FIG. 2 in dotted lines, while the drive pin 8 is carried along into the position in accordance with FIG. 6 by means of pivot axis 1 and lock ring 7.

During the course of this shifting movement the cutter shield is held in engagement with the drive pin 8 by the spring 11 which engages the lock ring 7, and consequently is moved along ahead of the cutter 3. Simultaneously the cutter shield is guided downwardly by the mantle earn which cooperates with the cam follower pin 14, so that on engaging the standard it has arrived in its lowest position below the plane of movement of the cutter. The cutter can now again swing along unimpededly in the plane of pivotal movement which has been freed until it reaches the operative position.

Having now described our invention with reference to the embodiment illustrated in the drawings, we do not wish to be limited thereto, but what we desire to protect by Letters Patent of the United States of America is set forth in the appended claims.

We claim:

1. Cutting device for sewing machines having a work supporting standard and comprising a cutter having an operative position on said standard and an inoperative position remote from said standard, a cutter supporting and operating means carrying said cutter and a vertically disposed pivot support arranged laterally of said standard pivotally supporting said cutter support with said cutter for movement along a rocking path into said operative and said inoperative position, a cutter shield having a position outside of said rocking path for said operative position of said cutter and including a shield support member of greater length than said cutter supporting means mounted on said vertically disposed pivot support, and shield actuating means including said cutter operating means and guiding conformations intermediate said cutter operating means and said shield support member operative in response to movement of said cutter operating means to guide said support member and thereby said shield vertically and angular into the said rocking path and into effective position in front of the cutting edge of said cutter in the inoperative position.

2. Cutting device for sewing machines having a work supporting standard and comprising a cutter having an operative position on said standard and an inoperative position remote from said standard, a cutter supporting and operating means carrying said cutter and a vertically disposed pivot support arranged laterally of said standard pivotally supporting said cutter support with said cutter for movement along a rocking path into said operative and said inoperative position, a cutter shield having a position outside of said rocking path for said operative position of said cutter and including a shield support member of greater length than said cutter supporting means mounted on said vertically disposed pivot support, and

shield actuating means including said cutter operating means and guiding conformations intermediate said cutter operating means and said shield support member operative in response to movement of said cutter operating means to guide said support member with said shield into the said rocking path and into effective position in front of the cutting edge of said cutter in the inoperative position, said rocking path being in a horizontal plane, said shield support member including a sleeve mounted on said pivot support and having a groove defining a mantle cam and said actuating means including a stationary pin in engagement with said groove for imparting axial movement to said sleeve and thereby said shield and a lock ring on said pivot support presenting a movable pin adapted to engage said shield support member for imparting rotating movement thereto.

3. Cutting device for sewing machines having a work supporting standard and comprising a cutter having an operative position on said standard and an inoperative position remote from said standard, a cutter supporting and operating means carrying said cutter and a vertically disposed pivot support arranged laterally of said standard pivotally supporting said cutter support with said cutter for movement along a rocking path into said operative and said inoperative position, a cutter shield having a position outside of said rocking path for said operative position of said cutter and including a shield support member of greater length than said cutter supporting means mounted on said vertically disposed pivot support, and shield actuating means including said cutter operating means and guiding conformations intermediate said cutter operating means and said shield support member operative in response to movement of said cutter operating means to guide said support member with said shield into the said rocking path and into elTective position in front of the cutting edge of said cutter in the inoperative position, said rocking path being in a horizontal plane, said shield support member including a sleeve mounted on said pivot support and having a groove defining a mantle cam and said actuating means including a stationary pin in engagement with said groove for imparting axial movement to said sleeve and thereby said shield and a lock ring on said pivot support presenting a movable pin adapted to engage said shield support member for imparting rotating movement thereto, said movable pin causing said groove to follow said stationary pin and forcing said shield to follow said cutter axially and angularly to said inoperative position.

References Cited in the file of this patent UNITED STATES PATENTS 1,812,245 Krell June 30, 1931 2,517,485 Henning Aug. 1, 1950 2,931,330 Pinkvoss Apr. 5, 1960 

1. CUTTING DEVICE FOR SEWING MACHINES HAVING A WORK SUPPORTING STANDARD AND COMPRISING A CUTTER HAVING AN OPERATIVE POSITION ON SAID STANDARD AND AN INOPERATIVE POSITION REMOTE FROM SAID STANDARD, A CUTTER SUPPORTING AND OPERATING MEANS CARRYING SAID CUTTER AND A VERTICALLY DISPOSED PIVOT SUPPORT ARRANGED LATERALLY OF SAID STANDARD PIVOTALLY SUPPORTING SAID CUTTER SUPPORT WITH SAID CUTTER FOR MOVEMENT ALONG A ROCKING PATH INTO SAID OPERATIVE AND SAID INOPERATIVE POSITION, A CUTTER SHIELD HAVING A POSITION OUTSIDE OF SAID ROCKING PATH FOR SAID OPERATIVE POSITION OF SAID CUTTER AND INCLUDING A SHIELD SUPPORT MEMBER OF GREATER LENGTH THANT SAID CUTTER SUPPORTING MEANS MOUNTED ON SAID VERTICALLY DISPOSED PIVOT SUPPORT, AND SHIELD ACTUATING MEANS INCLUDING SAID CUTTER OPERATING MEANS AND GUIDING CONFORMATIONS INTERMEDIATE SAID CUTTER OPERATING MEANS AND SAID SHIELD SUPPORT MEMBER OPERATIVE IN RESPONSE TO MOVEMENT OF SAID CUTTER OPERATING MEANS TO GUIDE SAID SUPPORT MEMBER AND THEREBY SAID SHIELD VERTICALLY AND ANGULAR INTO THE SAID ROCKING PATH AND INTO EFFECTIVE POSITION IN FRONT OF THE CUTTING EDGE OF SAID CUTTER IN THE INOPERATIVE POSITION. 